1. Field of the Invention
The present invention relates generally to microminiature electronic elements and particularly to an improved design and method of manufacturing a multi-connector assembly having noise shielding and internal electronic components.
2. Description of Related Technology
Multi-connector assemblies are well known in the electronic connector arts. As shown in FIGS. 1a-1c, such assemblies 100 typically comprise a number of rows 101 and columns 103 of individual connectors 104 (such as the RJ 11 or RJ 45 type) arranged so as to allow the simultaneous insertion and connection of multiple modular plugs (not shown) into the plug recesses 106 of the connectors. See, also, for example, U.S. Pat. No. 6,193,560 issued Feb. 27, 2001, co-owned by the Assignee hereof. There are several major considerations in designing and manufacturing such a multi-connector assembly, including: (i) shielding the individual connectors against externally generated electromagnetic interference (EMI) or “noise”, (ii) the size or volume consumed by the assembly, (iii) reliability, and (iv) the cost of manufacturing.
With respect to EMI, prior art multi-connector assemblies such as that of FIGS. 1a-1c are typically constructed from a molded plastic housing 102 in which the individual connectors 104 are integrally formed, and an external metallic noise shield 172 which wraps around or envelops much of the external surface area of the connector housing. This approach of using merely an external “wrap-around” noise shield 172 has several drawbacks, however. Specifically, such an arrangement does not provide complete or even near-complete shielding of the individual connectors 104 in the assembly 100, since the bottom surface 111 of the connector housing is often left largely unshielded due to concerns of reduced reliability due to electrical shorting between the connector conductors 120 and the metallic shield 172. This “gap” in the shielding decreases the overall performance of the connector assembly 100 by decreasing the signal-to-noise ratio (SNR) resulting from the increased noise. Additionally, such wrap-around external shields 172 do not address the issue of cross-connector noise leakage; i.e., noise radiated by the components of one connector in the assembly interfering with the signal of the other connectors, and vice-versa.
Accordingly, attempts have been made to provide additional shielding between the individual connectors in the assembly, including providing one or more shield elements between the conductors thereof. See U.S. Pat. No. 5,531,612 entitled “Multi-port Modular Jack Assembly” issued Jul. 2, 1996 ('612 patent). While an improvement over the aforementioned prior art devices using only a “wrap around” noise shield, the invention of the '612 patent suffers from several disabilities, including inter alia: (i) no provision for noise shielding between the connector assembly and the substrate (e.g., PCB) to which it is mounted; and (ii) the use of substantially perpendicular molded conductor inserts 140a, 140b or carriers (two per connector) which complicate the manufacture and assembly of the device and increase cost of manufacturing. Additionally, the device disclosed in the '612 patent does not include filtering, voltage transformation, or other electronic components for each connector integrally within the assembly itself; hence, no provision for physically accommodating and shielding such components is provided.
A related issue concerns the use of noise-emitting sources such as light emitting diodes (LEDs) 160 in the connectors of the assembly; such components are also potentially significant sources of EMI, and therefore should in many cases be shielded from the other connector components in order to achieve optimal performance. Prior art multi-connector assemblies such as that of FIGS. 1a-1c or the '612 patent typically have no provision for shielding of the LEDs from the other connector assembly components, a significant disability. Rather, the LEDs 160 are commonly disposed physically within the external shield 172, often in close proximity to other connector components such as the conductors 120 and in-line electronic filters (not shown).
Since in general consumers are highly sensitive to the cost and pricing of multi-connector assemblies, there exists a constant tension between producing a multi-connector assembly which has the best possible (noise) performance with the lowest possible cost. Hence, the most desirable situation is that where comprehensive external and cross-component noise shielding can be implemented with little impact on the cost of the finished product as a whole. Additionally, since board space (“footprint”) and volume are such important factors in miniaturized electronic components, improvements in performance and noise shielding ideally should in no way increase the size of the component. Lastly, the connector assembly must also optimally include signal filtering/conditioning components such as inductive reactors (i.e., “choke” coils), transformers, and the like with no penalty in terms of space or noise performance.
Based on the foregoing, it would be most desirable to provide an improved multi-connector assembly and method of manufacturing the same. Such an improved assembly would be reliable, and provide enhanced external and intra-connector noise suppression, including suppressing noise between integral electronic components and the substrate to which the assembly is mounted, while occupying a minimum volume. Additionally, such improved device could be manufactured easily and cost-efficiently.